Five ways researchers are using drones and remote sensing to stop terrestrial invasive species in Minnesota

September 10, 2019

On September 25, MITPPC will be hosting a free public event highlighting the role of drones in cutting-edge invasive species research across Minnesota. Attendees will hear from University of Minnesota faculty, aerospace industry experts and local land managers. (It’s not too late to reserve your seat!)

Below are five ways our researchers and regional partners are using drones to fight invasive species on the ground.

A researcher holds a portable spectroradiometer, which is used for remote sensing of oak wilt in the field. (Credit: Caro Silvola, MITPPC)

1. Early detection of a deadly oak disease in Minnesota forests

Oak wilt is a disease caused by an invasive fungus that can move between trees. Early detection is critical to stopping the spread, but it can be difficult with symptoms that mimic those of drought stress and other diseases.

To help forest managers find infected trees quickly, an MITPPC-funded research team led by biologists Jeannine Cavender-Bares, Rebecca Montgomery and Jennifer Juzwik have turned to a remote surveillance technique called hyperspectral imaging. Soon, they will be testing their methods with the use of drones flown above a forest canopy.

The team believes this work will allow them to remotely identify oaks among other tree species as well as tell the difference between healthy and sick trees in a forest plot. Read more about what hyperspectral imaging is, and what other oak wilt questions the group is answering at our recent feature, "Saving America's Tree".

Cavender-Bares will be speaking about her work at the ‘Drones in Invasive Species Management’ symposium on September 25. Register here.

2. Scouting for aphids in soybean fields

The soybean aphid is the most important insect pest of soybeans in Minnesota, and estimating the number of aphids across hundreds of acres is no small feat. Growers can estimate populations by conducting a zig-zag walk through the field, sampling the leaves of 30-40 plants for every 50 acres. Experts recommend weekly scouting from June through August, and treatment when numbers hit an average of 250 aphids per plant and growing.

MITPPC-funded Extension entomologist Robert Koch is looking to use drone imaging to make the scouting process easier for farmers, and ensure treatment only happens when necessary.

“The hope is that if we can make scouting a more efficient process, growers and consultants will be more likely to adopt it,” said Koch. “That way, they can make decisions about when to apply insecticides based on a measure of the pest’s actual pressure in the field rather than spraying based on a calendar date.”

Koch’s drones can determine the health of a soybean plant based on the way that light energy is reflected back to a drone.

“We have to be thinking differently about the management of the soybean aphid,” said Koch. “We’ve been managing it the same way for all these years and that has to change.”

A drone used for capturing the migration patterns and flight behaviors of the invasive spotted wing drosophila.

3. Tracking the migration and flight patterns of an invasive fruit fly that affects local berry and wine grape production

The spotted wing drosophila (SWD) is an invasive fruit fly that has affected the productivity of fruit growers across Minnesota. One of the major roadblocks to developing better management recommendations for the insect is a dearth of knowledge about the insect’s biology and behaviors in its new, northern environment.

It’s not likely, for example, that SWD can survive Minnesota’s extreme winters – but no one is sure what the flies are doing during that time. They could be seeking shelter in warm spaces like greenhouses or other protected structures, avoiding the problem altogether by migrating to Minnesota at the start of each season from warmer states or some combination of the two.

Along with information about how the flies move at a more local level between fields, Tran’s migration research will be used to develop population forecasting tools for raspberry and grape growers. Her project is just one portion of a larger MITPPC-funded venture focused on spotted wing drosophila’s impact on the Minnesota raspberry industry, led by Drs. Mary Rogers, Gigi DiGiacomo, and Bill Hutchison.

Read more about the team’s work with spotted wing drosophila (SWD) at the project page.

4. Mapping the distribution of invasive weeds across a large landscape

Oriental bittersweet is a bright-berried, invasive vine that has been wreaking havoc on forests around the Twin Cities metro and into southeastern Minnesota.

MITPPC partners at the University of Minnesota, Minnesota Department of Agriculture, Conservation Corps of Minnesota and St. Croix River Association have used quadcopter-style drones to help detect oriental bittersweet from the air, in lieu of sending search parties out on foot across steep terrain.

These efforts could help pinpoint areas for treatment on hilly areas, river valleys and bluffs. With the help of technology like drones for early detection efforts, experts are hopeful for eradication of oriental bittersweet in the state.

Remote sensing expert Atena Haghighattalab specializes in working with these massive field testing environments, and she uses drone imagery to help analyze results quickly. Her field of phenomics focuses on understanding how new crop breeding lines perform in a natural field environment.

Haghighattalab is the current Phenomics Lead for UMN CFANS. She will be speaking about using drones in large-scale crop breeding programs at the ‘Drones in Invasive Species Management’ symposium.

Funding for these projects was provided by the Environment and Natural Resources Trust Fund as recommended by the Legislative and Citizen Commission on Minnesota Resources.